Rationale:

• Limited information about OTC drugs and herbal preparations limits their use in treating obesity.

Evidence:

• A 12-week randomized clinical trial with Garcinia cambogia, which provides hydroxycitrate, showed no greater weight loss than with placebo (533).
• A 4-week randomized clinical trial with chitosan showed no significant weight loss (534). Fecal fat loss was not increased by chitosan (535).
• Calcium supplements in healthy children do not affect weight gain (536).
• A 12-week double-blind, randomized controlled trial of green tea extract vs. placebo reduced body fat, systolic blood pressure, and LDL cholesterol in a Japanese study (537).
• Both green tea extract and higher protein intake improved weight maintenance, but they were not additive (538).
• A 1-year trial of conjugated linoleic acid was no more effective than placebo in preventing weight regain (539).
• A novel fat emulsion (Olibra) containing fractionated palm oil (4%) and oat oil (2.5%) was reported to slow weight regain after weight loss (540).
• A systematic review suggests that acupuncture produces modest weight loss of 1.56 to 1.90 kg compared to controls (541).

Comments:

• Ephedra-containing dietary supplements were removed from the market by the FDA because of safety concerns (542), but this was overturned in a court trial.
• Health concerns exist with ma huang with and without caffeine (542; 543).
• A meta-analysis of chitosan showed that studies that met the allocation concealment criteria were larger, of longer duration, and produced smaller differences in weight (544).
• A small, randomized clinical trial of an herbal product containing ephedra, caffeine, Garcinia cambogia, and green tea extract produced 7.18-kg weight loss vs. 2.25 kg for placebo after 9 months (545).
• Many dietary supplements are sold with the goal of helping people lose weight. The legislative authority for this class of products is the 1995 Dietary Supplement and Health Education Act, which exempted these products from premarketing FDA scrutiny. In contrast, OTC products are approved by the FDA before marketing and have ongoing follow-up during their postmarketing phase. Dietary supplements do not need FDA approval; do not undergo a premarketing approval, efficacy, or safety process; and are not subject to postmarketing surveillance unless toxicity appears.